In the printed circuit industry, a mask bearing an image in the form of a circuit pattern is known as a phototool. A photosensitive material can be disposed between the phototool and a metal substrate, and radiation applied through the phototool to form the negative of the image in the form of hardened photosensitive material. The phototool is then separated from the hardened and unhardened photosensitive material, and any unhardened photosensitive material removed to leave the hardened negative image on the substrate. It is desirable for a phototool to be durable enough such that it can be used repeatedly with accurate reproduction of a circuit pattern.